function [ A B C D ] = getTwiddleFFT( N,filterLen )
%CREATINGCIRCRECON Summary of this function goes here
%   Detailed explanation goes here
    s = -filterLen + 1;
  w =  dbaux(filterLen);
    [lpd,hpd,lpr,hpr] = orthfilt(w); 
    
    vecLp = zeros(1,N);
    vecHp = zeros(1,N);
    vecLp(1:length(lpr)) = lpr;
    vecHp(1:length(hpr)) = hpr ;
  
    vecLp = ifft(circshift(vecLp',s));
    vecHp = ifft(circshift(vecHp',s));
    
    A = vecLp(1:N/2);
    C = vecLp((N/2+1):end);

	B = vecHp(1:N/2);
    D = vecHp((N/2+1):end);

end

